A: Nano-Photonics

After the invention of the laser, optics turned into photonics. In today's telecommunication technology, photons have already become the main carrier of information - although even today, mostly "conventional" technologies such as fiber optics and low index-contrast optical wave guides are employed.

Other attractive prospects for photonics-based information technologies arise from the fact that optically active nanostructures, e.g., semiconductor quantum dots, allow to store information in individual coherent states or coherent superpositions thereof. This opens up the wide field of quantum information processing - especially if one succeeds in the coherent preparation and manipulation of the electronic spin in quantum dots.

The vision of CFN research area A "Nano-Photonics" is to bring a number of recently emerged revolutionary theoretical concepts "down to earth" and eventually make them applicable in terms of functional nanostructures. We focus on periodic optical structures such as three-dimensional photonic band gap materials or metamaterials in project A1: Photonic Crystals and on spin-optoelectronics using quantum dots in project A2: Spin-Optoelectronics. Usable photonic devices based on these concepts as well as on others are investigated in project A4: Nano-Photonic Devices. Device examples are biosensors based on optical microresonators, superconductor-based single-photon detectors, organic photodetectors, ultrafast silicon-based modulators, and plasmonic modulators.